FOREWORD

In 1980, as part of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended, also known as the Superfund law, Congress created the Agency for Toxic Substances and Disease Registry (ATSDR). The Superfund is an amount of money used to investigate and--when necessary--clean up hazardous waste sites. The US Environmental Protection Agency (EPA) works with the individual states to investigate hazardous waste sites. The EPA can place sites on the National Priorities List (NPL), thus qualifying them for cleanup with Superfund money.

Since 1986, ATSDR has been required by the Superfund law to conduct a public health assessment at each of the sites on the National Priorities List (NPL). The assessment determines whether people are being exposed to hazardous substances and, if so, whether that exposure is harmful and should be stopped or reduced. The US Navy sites under review in this public health assessment are not NPL sites. But ATSDR can conduct public health assessments at the request of concerned individuals. Such requests are initiated through an ATSDR process known as a petition. This public health assessment, and related ATSDR public health actions currently underway in Vieques result from a petition submitted by a resident of the Isla de Vieques, Puerto Rico.

Exposure: As the first step in the assessment process, ATSDR scientists review site environmental data to determine the types of contamination, their quantity and location, and how people could come into contact with them. Generally, ATSDR does not collect its own environmental sampling data; it usually reviews information provided by EPA, other government agencies, businesses, and the public. When sufficient environmental information is not available, ATSDR scientists will indicate what further sampling data is needed.

Health Effects: If, however, the environmental data shows that people have or could come into contact with hazardous substances at the site, ATSDR scientists evaluate whether any harmful effects could result from these exposures. Their report will focus on public health, or the health impact on the community as a whole, rather than on individual risks. Again, ATSDR generally makes use of existing scientific information. This can include the results of medical, toxicologic and epidemiologic studies, as well as data collected in disease registries. Because the science of environmental health is still developing, information about the health effects of certain substances is sometimes not available. When this happens, the report will suggest what further research studies are needed.

Conclusions: The report will present conclusions about the level of health threat, if any, posed by a site and will recommend ways to stop or reduce that threat. Because ATSDR is primarily an advisory agency, the report will usually identify those actions that should be undertaken by EPA, other agencies or responsible parties, or by ATSDR's research or education divisions. If, however, the health threat is urgent, ATSDR can issue a public health advisory warning of the danger. ATSDR can also authorize health education or health effects pilot studies, full-scale epidemiology studies, disease registries, surveillance studies, or research about specific hazardous substances.

Interactive Process: The health assessment process is interactive. ATSDR solicits and evaluates information from city, state, and federal agencies, from companies responsible for cleaning up the site; and from the community. ATSDR then publicly shares its conclusions. State and federal agencies review and comment on an early version of the report to make sure the data they have provided is current and accurately presented. After learning of ATSDR's conclusions and recommendations, agencies will sometimes begin to act on them--even before the final release of the report.

Community: ATSDR also wants to learn what local citizens know about the site and what concerns they have about its effect on their health. Accordingly, throughout the evaluation process ATSDR gathers information and comments from the people who live or work near a site, including area residents, civic leaders, health professionals, and community groups. To ensure the report responds to the community's health concerns, an early version is also distributed to the public for its comments. Comments received from the public are addressed in the report's final version.

Comments: If, after reading this report, you have questions or comments, we encourage you to send them to us.

Letters should be addressed as follows:

Attention: Chief, Program Evaluation, Records, and Information Services Branch, Agency for Toxic Substances and Disease Registry, 1600 Clifton Road (E-56), Atlanta, GA 30333.

Summary

The residents of Vieques are concerned that military training activities at the Live Impact Area (LIA) are adversely affecting their health. Previous studies have reported some indication of heavy metals in fish and shellfish, which are eaten by the residents of Vieques. To address this pathway, the Agency for Toxic Substances and Disease Registry (ATSDR) worked with the US Environmental Protection Agency's Environmental Response Team (EPA/ERT) to collect and analyze fish and shellfish from the coastal waters and near shore land on Vieques to determine whether fish and shellfish muscle tissues contain levels of heavy metals and explosives compounds that would adversely affect public health. Based on research by Universidad Metropolitana (Caro et al. 2000), discussions with the petitioner and residents of Vieques, and information provided in the Vieques Special Commission Report (Government of Puerto Rico 1999 as cited in Navy 2000b), ATSDR collected grouper (Epinephelus sp.), snapper (Ocyurus chrysurus and Lutjanus sp.), parrotfish (Scaridae family), grunt (Haemulon sp.), goatfish (Mullidae family), land crabs (Cardisoma guanhumi), queen conch (Strombus gigas), and spiny lobster (Panulirus argus) as commonly caught and consumed species. In addition, to address a specific community concern, ATSDR collected one honeycomb cowfish (Lactophrys polygonia) from the fish market. For reference, Appendix E contains pictures of the fish species collected.

From July 16-20, 2001, these commonly consumed fish and shellfish were collected from six locations on Vieques. Fish were collected from reefs to the north of the LIA (Location 1), from a sunken Navy vessel to the south of the LIA (Location 2), from reefs to the south of Esperanza (Location 3), from reefs to the north of Isabel Segunda (Location 4), from a fish market in Isabel Segunda (Location 5), and from reefs to the west of the Laguna Kiani Conservation Zone on the west end of Vieques (Location 6). Lobsters were collected from Locations 1, 3, and 5. Conch were collected from seagrass beds located in close proximity to Locations 1, 2, 3, and 6. Land crabs were collected from Locations 1, 2, and 6. Fiddler crabs were collected from Locations 1 and 2.

During the sampling event, the EPA/ERT divers noted that all sample locations supported diverse populations of marine organisms that appeared healthy and that with very few exceptions, most of the organisms collected appeared to be healthy.

Several metals were detected in the fish and shellfish from Vieques. Using this data, ATSDR evaluated three specific exposure situations for both adults and children living on Vieques:

1. According to the survey conducted by Universidad Metropolitana, almost half the residents of Vieques eat fish one or two times a week. However, about 16% responded that they eat fish five or more times a week (Caro et al. 2000). To be most protective of the entire residential population, ATSDR evaluated whether eating fish and shellfish from Vieques on a daily basis would result in harmful health effects.
2. Individual metals in individual species of fish and shellfish varied from location to location (ATSDR 2002). Therefore, ATSDR evaluated whether eating fish and shellfish from any of the sample locations would result in harmful health effects.
3. Universidad Metropolitana reported that yellowtail snapper was the most commonly caught and consumed species of fish (Caro et al. 2000). In addition, several Vieques fishermen and residents indicated to ATSDR that snapper was more commonly sought after, caught, and consumed than any other species of fish. Therefore, ATSDR evaluated whether eating snapper on a daily basis would result in harmful health effects.

ATSDR concluded that:

1. It is safe to eat a variety of fish and shellfish every day.
   
   
2. It is safe to eat fish and shellfish from any of the locations sampled, including from around the LIA and the sunken Navy target vessel.
   
   
3. It is safe to eat the most commonly consumed species, snapper, every day.

I. Introduction

In May 1999, a resident of Isla de Vieques (Vieques), Puerto Rico, requested (petitioned) the Agency for Toxic Substances and Disease Registry (ATSDR) to determine whether hazardous substances from the detonation of munitions at the United States Navy (Navy) bombing range on the island pose a public health threat. In August 1999, ATSDR conducted an initial site visit to Vieques to meet with the petitioner, tour the island and bombing range, and gather available environmental data. As a result of this site visit, ATSDR accepted the petition and since has been investigating public health concerns related to the Navy's training activities on Vieques.

ATSDR is responding to this petition in a series of public health assessments (PHAs). PHAs examine chemicals that enter the environment, how the chemicals move through the environment, and the levels of chemicals that residents might encounter. ATSDR then uses this information to determine whether residents are exposed to levels of contamination that might cause health problems.

This PHA addresses the public health implications from eating fish and shellfish from the coastal waters and near shore land of Vieques. The fish and shellfish were analyzed for explosives compounds and heavy metals. Explosives compounds are not naturally occurring in fish and shellfish. Whereas, heavy metals are commonly detected in fish and shellfish tissue because seafood tends to accumulate metals that are naturally present in the environment (ATSDR 1999a; ATSDR 2000a; EPA 2001a). Therefore, eating fish can be a major source of one's exposure to metals. In fact, many states have issued advisories against eating fish or shellfish because of the metal content (EPA 2000). ATSDR focused this evaluation on the types of fish and shellfish that the community commonly catches and consumes (based on research by Universidad Metropolitana (Caro et al. 2000), discussions with the petitioner and residents of Vieques, and information provided in the Vieques Special Commission Report (Government of Puerto Rico 1999 as cited in Navy 2000b)).

I. Introduction

In May 1999, a resident of Isla de Vieques (Vieques), Puerto Rico, requested (petitioned) the Agency for Toxic Substances and Disease Registry (ATSDR) to determine whether hazardous substances from the detonation of munitions at the United States Navy (Navy) bombing range on the island pose a public health threat. In August 1999, ATSDR conducted an initial site visit to Vieques to meet with the petitioner, tour the island and bombing range, and gather available environmental data. As a result of this site visit, ATSDR accepted the petition and since has been investigating public health concerns related to the Navy's training activities on Vieques.

ATSDR is responding to this petition in a series of public health assessments (PHAs). PHAs examine chemicals that enter the environment, how the chemicals move through the environment, and the levels of chemicals that residents might encounter. ATSDR then uses this information to determine whether residents are exposed to levels of contamination that might cause health problems.

This PHA addresses the public health implications from eating fish and shellfish from the coastal waters and near shore land of Vieques. The fish and shellfish were analyzed for explosives compounds and heavy metals. Explosives compounds are not naturally occurring in fish and shellfish. Whereas, heavy metals are commonly detected in fish and shellfish tissue because seafood tends to accumulate metals that are naturally present in the environment (ATSDR 1999a; ATSDR 2000a; EPA 2001a). Therefore, eating fish can be a major source of one's exposure to metals. In fact, many states have issued advisories against eating fish or shellfish because of the metal content (EPA 2000). ATSDR focused this evaluation on the types of fish and shellfish that the community commonly catches and consumes (based on research by Universidad Metropolitana (Caro et al. 2000), discussions with the petitioner and residents of Vieques, and information provided in the Vieques Special Commission Report (Government of Puerto Rico 1999 as cited in Navy 2000b)).

II. Background

Vieques is the largest offshore island in the Commonwealth of Puerto Rico. Vieques is 20 miles long, 4.5 miles at its widest point, and about 33,000 acres (or 51 square miles) in area. Figure 1 shows the location of Vieques and surrounding islands. As the figure illustrates, the nearest island to Vieques is the main island of Puerto Rico, approximately 7 miles to the west. The island of Culebra is roughly 9 miles north. St. Thomas, St. John, St. Croix, and other US Virgin Islands are all 20 miles or more northeast and southeast of Vieques.

Land Use

The detailed map in Figure 2 illustrates land use in Vieques. The western portion of Vieques is the former Naval Ammunition Support Detachment (NASD). Prior to May 2001, the Navy used this 8,200 acres for limited Navy operations (e.g., ammunition storage, rock quarry, communication facilities, and Navy support buildings) (IT Corporation 2000). In May 2001, the Navy transferred most of the NASD to the Isla de Vieques, the Puerto Rico Conservation Trust, and the US Department of the Interior, but retained about 100 acres of the former NASD lands for radar and communication facilities (Navy 2001a). Some NASD areas were leased to local farmers for cattle grazing and other agricultural purposes (see Picture 1).

The central 7,000 acres of Vieques houses the entire residential population of the island, mostly in the towns of Isabel Segunda and Esperanza. Vieques land uses include residential, agricultural, commercial, and industrial. In the past, sugarcane was the principal crop. Other crops have included coconuts, grains, sweet potatoes, avocados, bananas, and papayas. In the 1960s and 1970s, manufacturing was important for the economy, beginning in 1969 with the construction of the General Electric plant (Bermudez 1998). But currently, only minimal manufacturing takes place on the island. Isabel Segunda and Esperanza, however, are home to commercial fishing fleets, and recently tourism has been increasing in economic importance.

Until May 2003⁽¹⁾ , the Navy owned roughly the eastern half of Vieques, which is divided into two sections: the Eastern Maneuver Area (EMA) and the Atlantic Fleet Weapons Training Facility (AFWTF).

• The EMA includes approximately 11,000 acres located immediately east of the residential lands. The Navy uses the EMA periodically for various combat training activities, such as conducting shore landing exercises and small arms training (CH2MHILL and Baker 1999; IT Corporation 2000). Camp Garcia, where Marine Corps and Navy personnel are temporarily stationed on Vieques, is within the EMA (see Picture 2). East of the EMA is the AFWTF (3,600 acres), which is further divided into three smaller sections of land:
  
  
• The western part of AFWTF was formerly known as the Surface Impact Area. Prior to 1978, the area was used as an impact area for artillery. It is heavily vegetated and almost completely undeveloped, except for dirt roads, a few observation posts and towers, and the main observation post (OP-1), located on Cerro Matias on the eastern side (see Pictures 3 and 4).
• The middle portion of AFWTF is the Live Impact Area (LIA), also commonly referred to as the bombing range. This roughly 900-acre tract contains the targets for aerial and naval bombardment. The LIA is sparsely vegetated and contains no structures--only surplus equipment (e.g., tanks, small airplanes, and trailers) the Navy uses as targets (see Pictures 5 and 6).
  
  
• The eastern tip of AFWTF is the Punta Este Conservation Zone. To preserve the unique upland forest scrub and evergreen scrub habitats, no Navy operations take place on this small piece of land. A variety of animals, including roseate terns and sea turtles, visit and nest there (see Picture 7).
  
  

Demographics

ATSDR examines demographic data (i.e., population information) to determine the number of people potentially exposed to environmental chemicals and to determine the presence of any sensitive populations, such as women of childbearing age, children, and the elderly. Demographic data also provide details on population mobility which, in turn, helps ATSDR evaluate how long residents might have been exposed to environmental chemicals.

Table 1 summarizes the 2000 US Census Bureau demographic data for Vieques. As the table shows, the 2000 Census reported that 9,106 people live on Vieques. This figure includes residents on both the residential lands and Navy property. Table 1 also specifies the number of residents in three potentially sensitive populations. According to several anecdotal accounts, the population of Vieques is not highly mobile; many are lifelong residents of the island.

As noted previously, most of the residents of Vieques live in the two largest towns on the island, Isabel Segunda and Esperanza (see Pictures 8 and 9). Although these towns are located relatively close to the Navy property, they are several miles removed from the LIA. Approximately 7.9 miles of Navy owned land provides a buffer zone between the LIA and populated areas of Vieques.

Climate

Vieques lies in the path of the easterly trade winds (i.e., winds blowing from east to west). The climate is tropical-marine, with temperatures averaging about 79 Fahrenheit (26.3 Celsius). Annually, the temperature ranges from an average of 76 Fahrenheit (24.6 Celsius) in February to 82 Fahrenheit (28 Celsius) in August. The average amount of precipitation is about 45 inches a year. The western part of the island receives a higher amount of rainfall (about 50 inches a year) than the eastern part (about 25 inches a year). The rainy season is from August through November while the remainder of the year is drier. Tropical storms are common from June to November (NCDC 1985-1994; Torres-Gonzalez 1989).

African Dust Storms

Through the natural occurrence of African dust storms, Vieques, together with the mainland of Puerto Rico and other Caribbean islands, receive an increase of airborne dust particles in the summer. Each year, large quantities of dust from the Sahara Desert and Sahel region in Africa are transported at high altitudes to the Caribbean Sea and southeastern United States. These dust storms can transport minerals, chemicals, bacteria, fungus spores, and possibly viruses and insects. Recent studies have begun to link declining coral reef health with fungi and bacteria found in African dust (e.g., the soil fungus, Aspergillus, causes a disease in sea fans; USGS 2000). The potential for adverse health effects to occur from African dust storms will be addressed in the Community Health Concerns Section of the Air Pathway Evaluation PHA.

Geology

Vieques was formed from igneous and volcanic rock, mostly granodiorite, quartz diorite, and some lavas which created the bedrock of the island. On most of the western half as well as the central portion of the eastern half of the island, the bedrock is exposed and weathered. Because of the weathering of the bedrock, gravel and sands wash downhill during storms. Over the years this material has gathered in valleys by the ocean, forming alluvial deposits (see text box for definition). Other portions of Vieques have ancient marine deposits from a time when the island was submerged. Today these deposits reveal areas with some limestone, sandstone, siltstone, and other sedimentary rocks at the surface. ATSDR's PHA focused on the soil pathway describes the geology and soils of Vieques in greater detail (ATSDR 2003).

Naval Operational History

The Navy has occupied portions of Vieques since 1941. In 1960, the Navy established targets on Vieques and began bombing practice (Navy 1990). The use of the LIA for air-to-ground and ship-to-shore training increased after the closing of the Culebra Island range in the mid-1970s.

Many different types of explosive and non-explosive ordnance (e.g., bombs, flares, rockets, projectiles, and small arms) have been used at Vieques. ATSDR's PHA focused on the soil pathway describes the types of military ordnance in greater detail (ATSDR 2003). Generally, Naval training exercises are most frequent in February and August with fewer exercises in April, May, November, and December. Range utilization statistics data from 1983 to1999 indicate that the Navy and other parties conducted exercises on Vieques between 159 and 228 days per year, with the total number of days not varying considerably from one year to the next. On average, 1,862 tons of ordnance were used at Vieques annually between 1983 and 1998. This ordnance, on average, contained 353 tons of high explosives (Navy 1999). ATSDR's PHA focused on the air pathway will describe ordnance use on Vieques in greater detail.

Two types of explosives were commonly used at Vieques (Young 1978). One explosive is made from organic nitrated compounds (i.e., only carbon, hydrogen, oxygen, and nitrogen). Examples include 2,4,6-trinitrotoluene (TNT), cyclotrimethylene trinitramine (RDX), cyclotetramethylene tetranitramine (HMX), tetryl, Explosive D, Composition B (RDX and TNT), Octol (HMX and TNT), and Composition A-3 (RDX and wax). The second kind of explosive contains aluminum in addition to the organic nitrated compounds. Examples include Tritonal (TNT and aluminum), H-6 (TNT, RDX, and aluminum), and Torpex (TNT, RDX, and aluminum).

Live ordnance has not been used on Vieques since April 19, 1999, when two 500-pound bombs were accidentally dropped near an observation post (OP-1) on the LIA, killing a civilian guard. In January 2000, the decision was made that the Navy could resume training on Vieques. The training is limited to 90 training days per year and the use of nonexplosive ordnance only. In May 2000, the Navy resumed training.

ATSDR Involvement at Vieques

Since its 1999 receipt of the petition requesting an evaluation of public health issues on Vieques, ATSDR has worked extensively to characterize the extent of environmental contamination and potential health effects and to respond to community needs. The following is a summary of ATSDR's past involvement on Vieques:

• Site visits. Since 1999, teams of ATSDR scientists and community involvement specialists have visited Vieques more than 10 times. These visits included site familiarization, identification of health concerns, collection of relevant site information, and collection of fish and shellfish for analysis. During two of the site visits, ATSDR personnel extensively toured the former NASD, EMA, and AFWTF, which included a ground and aerial tour of the LIA.
• Community involvement. Defining community concerns is an essential step in the public health assessment process. To define specific environmental health issues of concern, ATSDR met several times with individuals, families, and many other residents of Vieques. ATSDR has also met with elected officials, physicians, nurses, school educators, fishermen, leaders of women's groups, pharmacists, and businessmen. Among other discussion topics, ATSDR inquired how the agency can most effectively provide public health information to the community. ATSDR plans to continue such community involvement activities at Vieques.
• Health education. Throughout the community involvement process, ATSDR has worked with physicians, nurses, and school officials to provide educational materials and to support the overall public health of Vieques residents. To date, the agency has hosted four physician workshops and one nurses' training workshop covering the various aspects of environmental health, including procedures for taking an exposure history The agency has also facilitated community education sessions on cancer. ATSDR intends to provide additional education sessions that will address topics such as air quality and asthma, nutrition and wellness, and environmental health.

In addition to the previous list of activities on Vieques, ATSDR has assessed the following public health issues:

• In October 2001, ATSDR released a PHA addressing contamination in drinking water supplies and groundwater (ATSDR 2001a). This report concluded that the public drinking water supply on Vieques poses no public health hazard. However, high nitrates and nitrites, most likely resulting from agricultural pollution, in one private drinking water well indicate a health concern for children and pregnant women if they drank water from that well. The report evaluates these health issues in greater detail. Copies are available by contacting ATSDR (1-888-42-ATSDR) and from records repositories on Vieques. The repositories are located at Biblioteca Publica (Calle Carlos Lebrum, Vieques), the Vieques Conservation and Historical Trust (Flamboyan Street, Vieques), and at the University of Puerto Rico's School of Public Health (San Juan, Puerto Rico).
• In July 2001, ATSDR, the Ponce School of Medicine, and the Centers for Disease Control and Prevention (CDC) sponsored an expert panel review to address whether an association existed between place of residence (Vieques or Ponce Playa) and morphological cardiovascular changes among fishermen. A second review by experts showed no indication of abnormal heart function attributable to pericardial thickening. The report summarizing the expert panel review was released in October 2001 (ATSDR and PSM 2001). Copies are available by contacting ATSDR (1-888-42-ATSDR).
• ATSDR continues to evaluate the public health implications of exposure to air contaminants. In a PHA released for public comment in November 2002, ATSDR addressed potential health issues resulting from air releases from the LIA, including wind-blown dust and the use of practice bombs, live bombs, and various other munitions.
• In February 2003, ATSDR released a PHA addressing public health implications from exposures to soils on Vieques (ATSDR 2003). ATSDR addressed exposures that the residential population might typically experience as well as exposures that individuals who lived on the LIA between April 1999 and May 2000 might have experienced. This document concluded that there is no evidence that residents are being exposed to harmful levels of contamination in the soil.

¹ As of May 2003, the former Navy portions of Isla de Vieques are under the control of the U.S. Fish and Wildlife Service.

III. Previous Research

This section of the PHA summarizes research previously conducted on Vieques that is directly related to the fish and shellfish sampling conducted by ATSDR and EPA/ERT. The next section of the PHA (Section IV) provides more details about ATSDR's sampling effort.

1. Biomagnification of Carcinogenic Metals in Crab Tissue, Vieques, Puerto Rico by Arturo Massol Deyá, Ph.D. and Elba Díaz, M.S. Casa Pueblo de Adjuntas and Universidad de Puerto Rico. January 12, 2000.

Summary

In November 1999, researchers from Casa Pueblo de Adjuntas, in cooperation with the Biology Department of Recinto Mayaguez at the University of Puerto Rico, sampled male fiddler crabs (Uca pugnax rapax) from Icacos and Anones Lagoons in the LIA and from Puerto Mosquito just east of Esperanza. The purpose of the research was to assess the potential transport of metals from the impact area to other ecosystems.

Researchers collected "close to 35" fiddler crabs at each location. They analyzed the extremities (levers and legs) separately from the body (shell and internal contents) for cadmium, chromium, cobalt, copper, lead, manganese, nickel, and zinc. Please see Table 2 for a summary of the results. The researchers compared the levels of the heavy metals detected in fiddler crabs in Icacos Lagoon to the levels in the sediments and reported that biomagnification (see text box for definition) of cadmium was occurring. They also noted that the average cadmium concentration exceeds the critical levels of concern for cadmium ingestion according to the US Food and Drug Administration (FDA) and the World Health Organization (WHO).

Conclusions

This research established that fiddler crabs contained evidence of heavy metals. However, fiddler crabs are not known to be a species that are eaten by the residents of Vieques. While the data from this report may be useful to evaluate ecological contamination, it has limited utility when trying to extrapolate into the human food chain. To evaluate human exposures to edible land-based shellfish, ATSDR sampled and analyzed land crabs (a species known to be consumed by the residents) during the fish and shellfish investigation in July 2001. The remainder of this PHA details ATSDR's sampling effort (Section IV) and evaluates whether eating land crabs, among other fish and shellfish species, would result in harmful health effects (Section V).

1. Toxicological Survey of Heavy Metals in Fish Populations, Vieques Island
   by Doris A. Caro, Ph.D.; Mei-Ling Nazario; and Noel Diaz. Universidad Metropolitana. June 2000.

Summary

Between December 1999 and April 2000, researchers from the School of Environmental Matters, Universidad Metropolitana, collected fish from fish markets on the northern and southern (Esperanza) coasts of Vieques and from the Parquera fish market in Lajas on the western side of the mainland of Puerto Rico. The focus of the research was to identify potential heavy metal contamination in fish species that are commonly eaten by the residents of Vieques.

To identify the most frequently consumed species, researchers administered a questionnaire to Vieques residents asking about their dietary habits. Fifty-one residents responded to the questionnaire. Of these, 10 people (19.6%) reported to eat fish never or occasionally, 24 people (47%) 1-2 times a week, 9 people (17.6%) 3-4 times a week, and 8 people (15.7%) five or more times a week. Based on responses to the questionnaire, the most commonly consumed species of fish include: colirrubia (yellow tail snapper, Ocyurus chrysurus), mero cabrilla (red hind, Epinephelus guttatus), peje puerco (triggerfish, Balistes sp.), sierra (cero, Scomberomorus regalis), capitán (not identified), cotorro (parrotfish, Scaridae family), chapín (trunkfish, Lactophrys sp.), bonito (skipjack tuna, Euthynnus pelamis), negra (blackfin snapper, Lutjanus buccanella), dolorado (not identified), chillo (silk snapper, Lutjanus vivanus), boquicolorao/ronco (white grunt, Haemulon plumieri), and sama (mutton snapper, Lutjanus analis).

Researchers collected a total of 78 fish--35 fish from fish markets in northern Vieques, 17 fish from fish markets in Esperanza, and 26 fish from fish markets in the Parquera area on the mainland of Puerto Rico. Species included: arrayao (lane snapper, Lutjanus synagris), boquicolorao, colirrubia, cotorro azul (blue parrotfish, Scarus coeruleus), cotorro rojo (stoplight parrotfish, Sparisoma viride), cotorro verde (redband parrotfish, Sparisoma aurofrenatum), mero cabrilla, mero mantequilla (coney, Epinephelus fulvus), and salmorete de altura (goatfish, Mullidae family). Fish fillet and skin samples were tested for arsenic, cadmium, lead, mercury, selenium, and zinc.

The researchers concluded that "based on the data obtained...we were not able to verify our hypothesis of potential bioaccumulation in the fish...there is no clear relationship between fish weight and size and their metal content" (Caro et al. 2000). They reported "high concentrations" of arsenic, mercury, selenium, and zinc; but low or no concentrations of cadmium and lead in the fish tissue samples. Please see Tables 3 and 4 for a summary of their analytical results.

Conclusions

1. Contaminant levels in crabs from two solid waste management units on Vieques National Wildlife Refuge (October 4, 2002)

Summary

In July 2001, US Fish and Wildlife Service (FWS) personnel sampled land crabs and fiddler crabs from two solid waste management units (SWMUs) in west Vieques (the former NASD) and from Sandy Point National Wildlife Refuge in St. Croix, as a control. The samples are whole body and were analyzed for pesticides and metals. The purpose of the research was to collect preliminary data about the level of contamination in the prey base (land crabs and fiddler crabs) for some aquatic birds (e.g., herons and egrets). FWS provided the analytical data to ATSDR for inclusion in this health assessment (FWS 2001a, 2001b). Please see Tables 5 and 6 for summaries of the fiddler crab and land crab data, respectively.

Conclusions

² It was not noted in the study by Caro et al. 2000 if the concentrations were reported as wet weight concentrations or dry weight concentrations, ATSDR is assuming they are wet weight concentrations.

IV. ATSDR'S Fish and Shellfish Sampling

The residents of Vieques are concerned that military training activities at the LIA are adversely affecting their health. Previous studies have reported "elevated" levels of heavy metals in fish and shellfish from Vieques (see Section III). People who regularly eat fish and shellfish may be exposed to these chemicals. The purpose of ATSDR's sampling and analysis activities was to determine whether the muscle tissues from commonly consumed fish and shellfish contain levels of heavy metals and explosives compounds that would adversely affect public health⁽⁴⁾. To assist in the activities, ATSDR worked with the US Environmental Protection Agency's Environmental Response Team (EPA/ERT) to collect and analyze fish and shellfish from the coastal waters and near shore land on Vieques.

1. Sample Locations

Fish and shellfish were collected from six locations on Vieques (see Figure 3). The following locations were chosen to represent productive fishing areas surrounding the island (Ecology and Environment 1986 as cited in Navy 2000b):

• Location 1. Fish and shellfish were collected from two small, near shore reefs to the north of the LIA on the east end of Vieques. The total area included in the sampling effort (the combined portions of each reef actually sampled by divers) was approximately 12,000 square meters. In addition, conch were collected from the sea grass bed and crabs were collected from the north end of the LIA.
  
  
• Location 2 consisted of two sections of a former Navy vessel, located approximately 100 yards meters, that had been used for military target practice, near shore to the south of the LIA on the east end of Vieques. The total area included in the sampling effort was approximately 10,000 square meters. In addition, conch were collected from the sea grass bed and crabs were collected from the west coast of Bahia Salina del Sur in the AFWTF.
  
  
• Location 3 consisted of three near shore reefs to the south of the town of Esperanza on the south shore of Vieques. Fish were collected at Bucky Reef and Patti Reef, and conch were collected from the seagrass bed north of Arena Reef. The total area included in the sampling effort was approximately 15,000 square meters.
  
  
• Location 4. Fish were collected from two near shore reefs to the northwest of the town of Isabel Segunda on the north shore of Vieques and from Mosquito Pier to the west of Isabel Segunda (see Picture 10). The total area included in the sampling effort was approximately 15,000 square meters.
  
  
• Location 5 was a fish market in the town of Isabel Segunda. No attempt was made to verify the area from which the fish and lobsters were caught, though the market staff stated that all fish and lobsters sold in the market were caught locally.
  
  
• Location 6. Fish were collected from an unnamed near shore reef off the southwest end of Vieques, in the vicinity of the Monte Pirata Conservation Zone. Conch were collected from a seagrass bed 500 meters northeast of the reef. The total area included in the sampling effort was approximately 15,000 square meters. In addition, land crabs were collected from the Laguna Kiani Conservation Zone on the west end of Vieques.
  
  

2. Methods

Species Collected

At each location, field personnel attempted to catch (or purchase, in the case of the fish market) five individuals from the following types of fish targeted for analysis: yellowtail snapper (Ocyurus chrysurus)/mutton or lane snapper (Lutjanus sp.), grouper/red hind/rock hind/coney (Epinephelus sp.), grunt (Haemulon sp.), parrotfish (Scaridae family), and goatfish (Mullidae family). In addition, field personnel attempted to catch or purchase five individuals of queen conch (Strombus gigas) and spiny lobster (Panulirus argus) at each sampling location. These fish and shellfish were determined to be commonly caught and consumed by the residents of Vieques, based on research by Universidad Metropolitana (Caro et al. 2000), discussions with the petitioner and residents of Vieques, information provided in the Vieques Special Commission Report (Government of Puerto Rico 1999 as cited in Navy 2000b), and visits to local fish markets. In addition, to address a specific community concern, ATSDR collected one honeycomb cowfish (Lactophrys polygonia ) from the fish market.

Field personnel planned to collect a sufficient number of individuals of blue land crab (Cardisoma guanhumi) on shore, adjacent to Locations 1, 2, and 6 and fiddler crab (Uca sp.) adjacent to Locations 1 and 2 to meet the tissue mass requirements for five replicates of the desired chemical analyses⁽⁵⁾ . For safety reasons, Navy technicians collected these crabs on the LIA and transferred them to field personnel the same day they were collected. Land crabs were determined to be a species eaten by the residents of Vieques, while fiddler crabs are not known to be a species that is eaten.

Table 7 summarizes the species of fish and shellfish that were collected from each sample location. For reference, Appendix E contains pictures of the species collected.

Quality Assurance and Quality Control

The data used in this investigation meets established EPA standards for adequate quality assurance and control measures for sampling procedures, chain-of-custody procedures, laboratory procedures, and data reporting. The analytical methods and detection limits established for this investigation were consistent with the study's objectives and were sufficient to enable a conservative evaluation of health implications. Appendix B contains more details concerning the sampling methods for ATSDR's fish and shellfish investigation.

3. Results

Organism General Health

All collected organisms were given a brief physical examination. However, the white grunts (H. plumieri) collected at the fish market had already had their gut cavities cleaned prior to sale; therefore, no internal examination was possible. All of the organisms collected from all of the sampling locations appeared to be healthy. Few had any obvious deformities or parasites, with the exception of the following.

• One french grunt from Location 6 was observed to have a deformed anal fin. The cause of the deformity (injury or growth defect) could not be determined. A graysby collected fromLocation 3 was observed to have a sunken belly, the cause could not be determined.
• External and internal parasites are common on reef fish, and in low numbers they are not an indication of a stressed system. A single fish was observed to have external parasites (isopods in the gill cavity of a bluestriped grunt from Location 3) and three fish were observed to have internal parasites (unidentified worms in the peritoneal cavity of two red hinds from the fish market and one coney from Location 6).

Chemical Analysis

Explosives compounds

Fish and shellfish tissues were analyzed for explosives compounds. No explosives compounds were detected in fish tissues from any sample location. Of the 42 shellfish samples, only fiddler crabs contained an explosives compound⁽⁶⁾ (HMX; see Table 5). No explosives compounds were detected in conch, lobster, or land crab samples from any location (see Table 9).

Metals

Fish and shellfish tissues were analyzed for heavy metals. Finding heavy metals in fish and shellfish is not unique to Vieques. Depending on the geology and chemical composition of the area, a variety of metals can be found in varying concentrations (e.g., EPA 2001a). If the levels are too high and pose a health concern, health agencies issue advisories against eating fish or shellfish. Of the heavy metals, mercury is the chemical of concern in the largest number of states (EPA 2000).

• Fish. Calcium, magnesium, potassium, selenium, and sodium were detected in every fish sample. Chromium, copper, and zinc were also frequently detected (in greater than 90% of the samples). Aluminum, arsenic, barium, and mercury were detected in 72-78% of the samples. Manganese and iron were detected in 65% and 60% of the samples, respectively. Lead and beryllium were detected in 35% and 19% of the samples, respectively. Cadmium, cobalt, nickel, silver, and vanadium were infrequently detected (in less than 10% of the samples) and antimony and thallium were not detected in fish. The ranges, averages, and frequency of detections are summarized in Table 8.
• Shellfish. Calcium, copper, magnesium, potassium, selenium, sodium, and zinc were detected in every shellfish sample and chromium was also frequently detected (95% of the samples). Aluminum, arsenic, barium, iron, and manganese were detected in 64-89% of the samples. Cadmium, mercury, silver, and vanadium were detected in 34-55% of the samples. Beryllium, cobalt, and lead were less frequently detected (in less than 25% of the samples). Antimony, nickel, and thallium were not detected in shellfish. The ranges, averages, and frequency of detections are summarized in Table 9.
• Fiddler crab. Antimony, beryllium, lead, mercury, and thallium were not detected in fiddler crabs and nickel was detected in 50% of the samples ⁽⁷⁾. The remaining metals were detected in every fiddler crab composite sample. The results are summarized under Live Impact Area in Table 5.

Methylmercury

One tissue sample from each of four species (red hind, white grunt, yellowtail snapper, and spiny lobster) collected from the fish market (Location 5) was analyzed for methylmercury. Methylmercury was detected in concentrations of 0.02-0.08 ppm (parts per million) in fish and 0.019 ppm in shellfish. Results are summarized in Tables 8 and 9.

³ The National Academy of Science notes that there are limitations to the usefulness of assessing human health concerns from analyses performed on nonedible portions of organisms or on the whole body (EPA 2000).

⁴ The purpose of ATSDR's sampling and health evaluation is to address any potential chemical contamination in the fish and shellfish; therefore, this public health assessment does not focus on any potential biological conditions (e.g., naturally occurring toxins in fish, diseases, parasites, or bacteria) that may afflict the fish and shellfish of Vieques.

⁵ Originally, ATSDR planned to collected blue land crabs and fiddler crabs from all six sampling locations. However, due to time constraints and logistical problems encountered during sampling, it was decided to limit the collection to these key locations.

⁶ Rinsing fiddler crabs of sand and dirt was inadvertently omitted prior to placing them into sample containers. The concentrations detected may not accurately represent the levels of HMX in fiddler crabs, rather the concentrations could be artificially elevated due to the external sand and dirt contamination.

⁷ Rinsing fiddler crabs of sand and dirt was inadvertently omitted prior to placing them into sample containers. The concentrations detected may not accurately represent the levels of metals in fiddler crabs, rather the concentrations could be artificially elevated due to the external contamination.

V. Evaluation of Fish and Shellfish From Vieques

A. Introduction

What is meant by exposure?

ATSDR's PHAs are driven by exposure or contact. Chemicals released into the environment have the potential to cause harmful health effects. Nevertheless, a release does not always result in exposure. People can only be exposed to a chemical if they come in contact with that chemical. If no one comes into contact with a chemical, then no exposure occurs, thus no health effects could occur. Often the general public does not have access to the area where the environmental release occurs; however, it is important to determine whether the chemicals are moving through the environment to locations where people could come into contact with them.

The means in which a chemical moves through the environment, and how people contact the chemical, defines an exposure pathway. ATSDR identifies and evaluates exposure pathways by considering how people might come into contact with a chemical. In this public health assessment, ATSDR is evaluating exposures from eating potentially contaminated fish and shellfish from the coastal waters and near shore land on Vieques.

If someone is exposed, will they get sick?

Exposure does not always result in harmful health effects. The type and severity of health effects that occur in an individual as the result of contact with a chemical depend on the exposure concentration (how much), the frequency and duration of exposure (how long), and the multiplicity of exposure (combination of chemicals). Once exposure occurs, characteristics such as age, sex, nutritional status, genetics, lifestyle, and health status of the exposed individual influence how that individual absorbs, distributes, metabolizes, and excretes the chemical. Taken together, these factors and characteristics determine the health effects that can occur as a result of exposure to a chemical in the environment.

Considerable uncertainty exists regarding the true level of exposure to environmental contamination. To account for that uncertainty and to protect public health, ATSDR scientists typically use high-end, worst-case exposure level estimates to determine whether harmful health effects are possible. ATSDR used the following conservative approaches throughout this public health evaluation:

• ATSDR evaluated human exposure from consuming fish and shellfish from Vieques on a daily basis (i.e., 365 days per year) although an earlier survey by Universidad Metropolitana showed that only 16% of residents of Vieques eat fish five or more times a week (Caro et al. 2000).
  
• ATSDR calculated averages using detected concentrations only and did not take into account nondetected values. This tends to overestimate the true average values.
  
• In estimating the amount of inorganic arsenic, the most harmful form, from total arsenic in fish and shellfish, ATSDR assumed that 20% of the total arsenic detected was the inorganic form, even though FDA recommends that 10% of total arsenic be considered inorganic and as little at 1% may be inorganic (ATSDR 2000a; Francesconi and Edmonds 1997; NAS 2001b; FDA 1993).
  

Therefore, the estimated exposure levels are much higher than the levels to which people are really exposed. If the exposure levels indicate harmful health effects are possible, a more detailed review of exposure, combined with scientific information from the toxicologic and epidemiologic literature about the health effects from exposure to hazardous substances, is performed.

What exposure situations were evaluated in this PHA?

ATSDR focused this health evaluation on the edible samples that ATSDR worked with EPA/ERT to collect in July 2001 from six locations on and around Vieques, including five families of commonly caught and consumed fish and three species of shellfish (see Table 7). Fiddler crabs were not included in the health evaluation because it is ATSDR's understanding that fiddler crabs are not a species that people eat. Each of the other species was considered to equally represent fish or shellfish that are directly consumed by the residents of Vieques.

ATSDR evaluated several different consumption scenarios depending on a person's fish and shellfish intake. According to the survey conducted by Universidad Metropolitana, almost half the residents of Vieques eat fish one or two times a week. However, about 16% responded that they eat fish five or more times a week (Caro et al. 2000). Therefore, to account for the variability in dietary habits, ATSDR estimated exposure from eating fish or shellfish 7 days a week, 5 days a week, 4 days a week, 2 days a week, and 1 day a week. The scenario of eating fish or shellfish 7 days a week was evaluated first. If this intake level revealed a potential health hazard, ATSDR determined what a safe consumption level would be.

Individual metals in individual species varied from location to location (ATSDR 2002). Thus, it is possible that if someone were to regularly eat fish or shellfish caught from a single location rather than from a variety of locations, his/her metal intake level could be different than the average (either higher or lower than the average). Therefore, in addition to determining an overall exposure for people who eat fish and shellfish from a variety of locations surrounding Vieques, ATSDR also examined whether eating fish or shellfish from any specific location would cause people to experience adverse health effects.

Universidad Metropolitana questioned the residents of Vieques about the types of fish they eat and reported that yellowtail snapper was the most commonly consumed species of fish (Caro et al. 2000). Through talking with several Vieques fishermen and residents, including the petitioner, ATSDR confirmed that snapper were most commonly sought after, caught, and consumed than any other species of fish. Therefore, ATSDR also considered a specific situation where people ate snapper on a daily basis.

For reference, Appendix A is a glossary of environmental and health terms and Appendix D describes in greater detail the methods and assumptions ATSDR used to estimate human exposure doses and determine health effects.

B. Public Health Evaluation

Is it safe to eat fish and shellfish from Vieques?

Yes, the fish and shellfish from Vieques are safe to eat. Even though several metals were detected in some of the fish and shellfish, the concentrations that were present were too low to be of health concern in virtually all exposure situations evaluated. Appendix D describes in greater detail how ATSDR reached this conclusion.

Is it safe to eat fish and shellfish every day?

Yes, it is safe to eat a variety of fish and shellfish from Vieques on a daily basis. ATSDR evaluated this specific scenario in detail in Appendix D and determined that eating a variety of fish and shellfish would not result in adverse health effects or an increase in the risk of developing cancer.

Arsenic levels in lobsters

ATSDR evaluated arsenic concentrations in lobsters in detail in Appendix D because of their tendency to store arsenic that is naturally present in the environment (research has shown that marine organisms tend to accumulate arsenic naturally present in seawater and food, rather than only accumulating arsenic due to local pollution; Eisler 1994 as cited in ATSDR 2000a). The lobsters from Vieques did not contain higher levels of arsenic than FDA's level of concern for average consumption (76 ppm; FDA 1993). However, based upon a hypothetical exposure situation (eating lobsters from Vieques every day), using highly conservative assumptions (ATSDR assumed that 20% of the total arsenic is in the inorganic form), ATSDR found that eating more than two meals of lobster each week for 70 years could theoretically lead to harmful health effects. However, this finding is debatable because (1) there is much uncertainty surrounding the level at which health effects are seen and (2) according to the scientific research, the amount of arsenic present in lobsters from Vieques is low enough to be controlled by normal metabolic processes in the body (ATSDR 2000a). Please see the arsenic discussion in Appendix D for more details.

ATSDR concludes that lobsters from Vieques are safe to eat and only under highly unlikely, hypothetical scenarios with several levels of conservatism built into the evaluation might the arsenic levels in lobsters be a problem for people eating more than two meals of lobster a week for a lifetime.

Is it safe to eat fish and shellfish from any location?

Yes, it is safe to eat fish and shellfish from all of the areas that ATSDR sampled. Despite the fact that some metals were detected in higher concentrations at different locations, none were so much higher that ATSDR would expect to see adverse health effects in people who may solely eat fish or shellfish from a single location (e.g., only from the fish market or only from areas around the LIA). In other words, even though there are differences in fish and shellfish body burdens between locations, these differences are too small to have an impact on public health.

Is it safe to eat the most commonly caught and consumed fish every day?

ATSDR determined that it is safe to eat snapper, reportedly the most desirable and most commonly consumed species, on a daily basis. In Appendix D, under the section titled Special Case: Snapper, ATSDR describes in greater detail how this conclusion was reached.

VI. Community Health Concerns

An integral part of the public health assessment process is addressing community concerns related to environmental health. ATSDR has been working with, and will continue to work with, the community to define specific health issues of concern. On multiple trips to the island, ATSDR has met with a variety of individuals and organizations, including local officials, physicians, nurses, pharmacists, leaders of women's groups, school educators, fishermen, and business people. ATSDR has also met with individual families. Meeting with a broad spectrum of community members is critical to determine health issues of concern and to assess the environmental health issues on Vieques.

General issues of health concern related to exposure to the soil, groundwater and public drinking water on Vieques were addressed in previously released PHAs (ATSDR 2001a, 2003). Another PHA will focus on addressing potential health issues resulting from air releases from the LIA. In addition, an expert review panel discussed the issue of whether an association existed between place of residence and heart disease among fishermen (ATSDR and PSM 2001). This section of the PHA addresses additional community concerns related to the fish and shellfish evaluation.

1. Concern: Drums on Sunken Navy Vessels

In November 1999, lawyers for the Puerto Rican Government contracted the University of Georgia to examine the health of the coral reefs. During their investigation they reported seeing two sunken vessels in Bahía Salina del Sur (south of the LIA) that contained hundreds of 55-gallon drums of unknown content. The community expressed concern that unknown substances could be leaking from these drums, contaminating the marine biota, and affecting the health of island residents.

The wreckage is actually the scuttled remains of the former USS Killen (Killen), a World War II destroyer which had been used as a target vessel. To address the concern, ATSDR sampled and analyzed fish and shellfish at this site in July 2001, as sample Location 2. Despite the common occurrence of unexploded ordnance, the site was home to a diverse population of apparently healthy fish and small head corals, and were surrounded by a large halo (the halo is a typical feature of reefs and underwater structures that is caused by grazing organisms leaving the shelter of the reef at night to feed on the surrounding seagrass beds) and a healthy turtle grass bed (see Appendix C for more details). In addition, ATSDR's evaluation determined that the fish and shellfish collected from Location 2 do not contain levels of metals or explosives compounds that would adversely affect the health of someone eating fish and shellfish from this area (see the Public Health Evaluation (Section VB) and Appendix D for more details).

The Navy and the Puerto Rico Department of Natural and Environmental Resources conducted personnel interviews and reviewed the document history of the sunken vessel. Personnel noted that despite numerous fly overs, no one observed any loss of residual material, oil slicks, or plumes coming from the wrecks (Navy 2000a). The investigative committee hypothesized that the 55-gallon drums were filled with air and placed on board to enhance buoyancy to keep the vessel afloat as long as possible (Navy 2000a). A second theory is that, in addition to being used for added target buoyancy, the 55-gallon drums were filled with sand or seawater and used as ballast to redistribute the weight of the vessel (i.e., add stabilization) after several alterations were made to remove much of the superstructure, armament, and heavy engineering components (Geo-Marine 2002).

In 2001, the Navy conducted a site investigation and characterized the biological organisms to assess the health of the marine species on and around the vessel and to assess potential impacts on the surrounding biota (Geo-Marine 2002). The overall conclusion was that the sunken vessel and its contents are not having a negative effect on the coral reef ecosystem, rather they are acting as a productive artificial reef habitat. The Navy will provide these results to EPA, who along with the Puerto Rico Environmental Quality Board (PREQB), will determine if further analysis is warranted.

2. Concern: Radiological Contamination from the former USS Killen

Concern has been expressed that because the Killen was a target ship during Operation HARDTACK, it could be contaminating the waters and biota around its resting place with radiation. Operation HARDTACK consisted of underwater nuclear tests in the Pacific in 1958. ATSDR received and reviewed information from the Navy regarding Operation HARDTACK and the involvement of the Killen. During the tests, the Killen was under constant water wash before and after the blasts to remove as much of the radioactivity as possible. A few days after each test, crews went on board, surveyed the ship, and manually decontaminated those areas needing additional treatment. There is no indication that sandblasting was used as the method of decontamination. After the nuclear tests, the Killen was towed to several locations including Hawaii, the Panama Canal Zone, and Norfolk, Virginia. From 1963 until 1975 the vessel was docked at Roosevelt Roads when not in use as a target vessel. The Killen was finally scuttled in 1975.

Radiation measurements collected in 1975 showed that the radiation intensity aboard ship was less than 0.75 microroentgen per hour (R/h) (SAIC 2002). Additional radiation readings were collected in March 2002. These readings were 0.33 R/h above background (SAIC 2002). For comparison, typical background is approximately 10 to 17 R/h, varying with location. Background levels of radiation result from several naturally-occurring sources, such as cosmic radiation from space and terrestrial radiation from radioactive materials in the ground.

An ATSDR health physicist also spoke with a Navy radiation scientist on this issue. As with typical nuclear tests, the predominate radioisotopes contributing to the radiation exposures was cesium 137 and strontium 90. Since the forms of cesium and strontium are reduced by half every 30 years, one can estimate that without any intervention of weather or man, the amount of these radioisotopes would be about 25% of the initial amount present on the Killen. This is seen in the data as the radiation readings taken in 2002 were more than 2 million times lower than the readings taken immediately after the tests.

Based on these observations, the radiation levels associated with the Killen are indistinguishable from the radiation associated with background levels naturally found in the environment (e.g., from cosmic and terrestrial sources) and do not pose any public health hazard to the residents of Vieques.

3. Concern: Metals Contamination from the former USS Killen

Concern was expressed regarding possible metals contamination of marine biota and of SCUBA divers visiting the remains of the Killen. Although ATSDR does not have specific water chemistry data from the vicinity of the Killen, there is no likely harmful exposure to chemicals that could result from SCUBA diving around the vessel. It should be pointed out that any sunken vessel can contain physical hazards that need to be considered in any diving activity. Also, because the area surrounding the Killen, and the Killen itself, have been targets in bombing and firing training, there could be hazard from unexploded ordnance.

There is a large body of information with which to address the concern that a sunken vessel promotes chemical contamination to the environment. Ships and other manmade objects such as defunct oil rigs, automobiles, and rail cars are frequently sought by natural resource agencies and private environmental organizations world-wide, to be used as artificial reef. Such structures form desirable habitat for marine biota and are common sites of recreational fishing and diving activities throughout the world. Although ATSDR does not endorse or recommend unauthorized diving in these waters, there is nothing unique in the construction of the former Killen that would suggest a human health hazard from exposure to metals by divers or marine biota. The following information on the environmental value of artificial reefs, including sunken vessels, was collected from publicly available Web sites.

Concern: Eating Boxfish

While on Vieques, ATSDR met with the petitioner, who at that time, specifically requested ATSDR to collect and analyze boxfish (family Ostraciidae; e.g., cowfish and trunkfish) from the fish market. At the request of ATSDR, the petitioner had compiled a list of fish caught and eaten on Vieques and reported that Chapín (boxfish) are the preferred fish to use as filling in pastelillos. Realizing that the results and conclusions would be limited, ATSDR agreed to collect a representative sample. A cowfish (honeycomb cowfish, Lactophrys polygonia) was purchased from the fish market for analysis. The results are presented in Table 10.

Of the fish sampled by ATSDR, the cowfish contained the highest concentrations of arsenic (29.3 ppm) and selenium (2.5 ppm). It should be noted that it is not unusual for different samples of the same species to contain varying chemical concentrations; therefore, other cowfish samples may contain higher or lower levels of these chemicals. However, consuming cowfish with the levels detected would not be expected to result in harmful health effects (see Appendix D for more details on the methods and assumptions ATSDR used to estimate human exposure doses and determine health effects).

Community members can direct additional health concerns to:

Community members can also telephone the ATSDR regional representatives in New York, New York, at (212) 637-4307 or call the toll-free telephone number, 1-888-42-ATSDR.

VII. Child Health Considerations

ATSDR recognizes that infants and children can be more sensitive to contamination of their food than adults because children are smaller, therefore childhood exposure results in higher doses of chemical exposure per body weight. Because children can sustain permanent damage if these factors lead to toxic exposure during critical growth stages, ATSDR as part of its public health assessment process is committed to evaluating their special interests at sites such as Vieques.

ATSDR specifically evaluated the exposure to children and determined that they can safely eat fish and shellfish from Vieques.

VIII. Conclusions

Through its sampling program and public health evaluation, ATSDR has drawn the following conclusions regarding the fish and shellfish of Vieques:

• ATSDR concludes that exposures to contaminants in fish and shellfish are not at levels expected to cause adverse health effects and thus the site does not pose a public health hazard. Because exposure is still possible to these low levels, ATSDR has categorized consumption of fish and shellfish as "no apparent public health hazard".
• During the July 2001 sampling, the appearance and general health of the reefs at all the sampling locations were noted. Although no quantitative data were collected, it was noted that all sample locations appeared to support diverse, healthy populations of marine organisms and that all reefs were in good condition.
• Field personnel briefly examined each fish and shellfish sample and reported that with very few exceptions, the organisms collected appeared to be healthy.
• Several metals were detected in some of the fish and shellfish from Vieques. However, the concentrations that were present were too low to be of health concern.
• Because individual metals in individual species varied from location to location, ATSDR evaluated whether eating fish or shellfish from any specific location would cause people to experience adverse health effects. The concentrations that were present at each location were too low to be of health concern.
• Universidad Metropolitana reported that yellowtail snapper was the most commonly consumed species of fish (Caro et al. 2000). In addition, several Vieques fishermen and residents indicated to ATSDR that snapper was more commonly sought after, caught, and consumed than any other species of fish. Therefore, ATSDR evaluated the specific scenario of people eating snapper every day and concluded that the chemical concentrations that were present in snapper were too low to be of health concern.
• Community members were concerned about the potential impact on marine biota in the vicinity of the former Killen located to the south of the LIA. Fish and shellfish from around the Killen were collected and analyzed during ATSDR's sampling effort. ATSDR concluded that the chemical concentrations in the fish and shellfish collected from this area were too low to be of health concern.
• The petitioner specifically requested ATSDR to collect and analyze boxfish (e.g. trunkfish, cowfish) from the fish market. A honeycomb cowfish was purchased for analysis. Based on the concentrations of chemicals detected, consuming cowfish with the levels detected would not be expected to result in harmful health effects.

IX. Public Health Action Plan

The Public Health Action Plan for Vieques contains a description of actions taken and those to be taken by ATSDR, the Navy, EPA, PREQB, and the Puerto Rico Department of Health (PRDOH). The purpose of the Public Health Action Plan is to ensure that this PHA not only identifies potential public health hazards, but also provides a plan of action to mitigate and prevent harmful human health effects that may be resulting from exposure to hazardous substances in the environment. The public health actions that are completed, ongoing, and recommended are as follows:

Actions Completed:

• In August 1999, ATSDR conducted an initial site visit to Vieques to meet with the petitioner, tour the island and bombing range, and gather environmental data. As a result of this site visit, ATSDR accepted the resident's petition and initiated the public health assessment process.
• In June and October 2000, ATSDR discussed with local health care providers their public health concerns and provided training regarding how to medically assess environmental exposures. During these visits ATSDR met with numerous residents of the island to discuss health concerns.
• In September 2000, ATSDR met with various agencies, including PRDOH, PREQB, EPA, the US Geological Survey, and the Navy, to gather data and to discuss the scope and nature of ATSDR investigations. ATSDR also met with the petitioner to tour various sites on Vieques and to update the petitioner on its efforts.
• In March 2001, ATSDR held a public availability session to meet individually with community members regarding the findings of the evaluation of drinking water and groundwater on Vieques.
• In April 2001, ATSDR toured Vieques both by land and by air with the principal purpose of identifying suitable areas to sample fish and shellfish off the coast of Vieques.
• In June 2001, the Navy, ATSDR, and their contractors collected air samples on Vieques to characterize levels of air contamination during air-to-ground bombing exercises.
• In July 2001, ATSDR, the Ponce School of Medicine, and CDC sponsored an expert review panel to address whether an association existed between place of residence (Vieques or Ponce Playa) and morphological cardiovascular changes among fishermen.
• ATSDR worked with EPA/ERT to collect and analyze fish and shellfish in the coastal waters and near shore areas of Vieques in July 2001. At this time, ATSDR also met with the petitioner to provide an update on ATSDR efforts.
• In September 2001, ATSDR conducted additional community involvement activities to inform participants of the scope of ATSDR investigations and seek additional community input. Continuing education and public health training was held for the nurses of Vieques and environmental health instruction was given to area parents and high school students.
• In October 2001, ATSDR released the Public Health Assessment for the Drinking Water Supplies and Groundwater Pathway Evaluation (ATSDR 2001a). This report concluded that the public drinking water supply on Vieques poses no public health hazard. However, high nitrates and nitrites, most likely resulting from agricultural pollution, in one private drinking water well indicate a health concern for children and pregnant women if they drank water from that well.
• In October 2001, ATSDR released a report summarizing the expert panel review addressing whether an association existed between place of residence and morphological cardiovascular changes among fishermen (ATSDR and PSM 2001). The panel found that the well-executed study showed no indication of abnormal heart function attributable to pericardial thickening.
• In November 2001, the Navy conducted a site investigation and characterized the biological organisms to assess the health of the marine species on and around the Killen and to assess potential impacts on the surrounding biota. EPA and PREQB will review the results and determine if further analysis is warranted.
• In February 2003, ATSDR released a PHA addressing public health implications from exposures to soils on Vieques (ATSDR 2003). This document concluded that there is no evidence that residents are being exposed to harmful levels of contamination in the soil.

Actions Ongoing:

• ATSDR continues to evaluate the public health implications of exposure to air contaminants. In a PHA released for public comment in November 2002, ATSDR addressed potential health issues resulting from air releases from the LIA, including wind-blown dust and the use of practice bombs, live bombs, and various other munitions.
• ATSDR is continuing to meet with various community members and organizations to receive concerns and exchange information. This effort will continue throughout the public health assessment process.
• ATSDR will continue to meet with local health care providers to discuss health concerns for the community and to provide educational materials for addressing the community's health needs.
• PRDOH is working on Vieques and in Puerto Rico generally to gather information regarding the incidence of cancer in Puerto Rico and on Vieques. That information will be added to the current cancer registry information.
• ATSDR will review cancer registry information and data gathered by PRDOH. The information will be evaluated as it relates to potential pathways of environmental exposure.

Preparers of Report

Jeffrey Kellam, M.S.
Geologist
Federal Facilities Assessment Branch
Division of Health Assessment and Consultation

Gary Campbell, Ph.D.
Environmental Health Scientist, Section Chief
Federal Facilities Assessment Branch
Division of Health Assessment and Consultation

Michelle Arbogast, M.S.
Environmental Scientist
Eastern Research Group

Field Sampling Team

Gregory Zarus, M.S.
Atmospheric Scientist
Exposure Investigations and Consultation Branch
Division of Health Assessment and Consultation

Alan Humphrey
Environmental Scientist
US Environmental Protection Agency Environmental Response Team

Daniel Cooke, M.S.
Marine Scientist
Lockheed Martin

References

The Agency for Toxic Substances and Disease Registry (ATSDR). 1990. Toxicological profile for copper. US Department of Health and Human Services; Atlanta, Georgia. December 1990.

ATSDR. 1994. Toxicological profile for zinc. US Department of Health and Human Services; Atlanta, Georgia. May 1994.

ATSDR. 1999a. Toxicological profile for mercury. US Department of Health and Human Services; Atlanta, Georgia. March 1999.

ATSDR. 1999b. Toxicological profile for cadmium. US Department of Health and Human Services; Atlanta, Georgia. July 1999.

ATSDR. 1999c. Toxicological profile for lead. US Department of Health and Human Services; Atlanta, Georgia. July 1999.

ATSDR. 2000a. Toxicological profile for arsenic. US Department of Health and Human Services; Atlanta, Georgia. September 2000.

ATSDR. 2000b. Toxicological profile for chromium. US Department of Health and Human Services; Atlanta, Georgia. September 2000.

ATSDR. 2001a. Focused public health assessment: drinking water supplies and groundwater pathway evaluation, Isla de Vieques, Puerto Rico. Division of Health Assessment and Consultation; Atlanta, Georgia. October 16, 2001.

ATSDR. 2001b. Toxicological profile for selenium. US Department of Health and Human Services; Atlanta, Georgia. September 2001.

ATSDR. 2002. Exposure Investigation. Isla de Vieques: Edible Fish. Vieques, Puerto Rico. Division of Health Assessment and Consultation; Atlanta, Georgia. 20002.

ATSDR. 2003. Public health assessment: soil evaluation, Isla de Vieques, Puerto Rico. Division of Health Assessment and Consultation; Atlanta, Georgia. February 2003.

ATSDR and the Ponce School of Medicine (PSM). 2001. Summary Report for the Vieques Heart Study: Expert Panel Review for a meeting held on July 12-13, 2001. Available from URL: http://www.atsdr.cdc.gov/NEWS/viequesheartreport.html.

Alabama Dept of Conservation and Natural Resources, Marine Resources Division, Alabama's Artificial Reef Program. 2003. Available from URL: http://www.dcnr.state.al.us/mr/reef_hist.htm. Last accessed 2/14/03.

Artificial Reefs of the Keys. 2003. Available from URL: http://www.bigshipwrecks.com/ Last accessed 2/14/03.

Austin Nutritional Research (ANR). 2001. Reference guide for minerals. Available from URL: http://www.realtime.net/anr/minerals.html. Last accessed September 19, 2001.

Bermudez W. 1998. Brief history of Vieques. Available from URL: http://www.vieques-island.com/hisindx.html.

Burger J, Cooper K, Saliva J, Gochfeld D, Lipsky D, and Gochfeld M. 1992. Mercury Bioaccumulation in Organisms from Three Puerto Rican Estuaries. Environmental Monitoring and Assessment 22:181-197. 1992.

Caro DA, Nazario M, Diaz N. 2000. Toxicological Survey of Heavy Metals in Fish Populations, Vieques Island. Universidad Metropolitana, School of Environmental Matters. June 2000.

CH2MHILL and Baker Environmental, Inc. (Baker). 1999. Results of the hydrogeologic investigation: Vieques Island, Puerto Rico. November 4, 1999.

Colin PL. 1978. Caribbean Reef Invertebrates and Plants. T.F.H. Publications, Inc. Ltd., Neptune City, NJ.

Department of the Navy (Navy), Atlantic Division. 1990. Water quality study at the US Atlantic Fleet Weapons Training Facility, Vieques Island, Puerto Rico: September 1990.

Navy. 2000a. Finding of no significant impact for inert naval surface fire support, air-to-ground bombing, amphibious landings, and simulated mine warfare training, to include August composite training unit exercise (COMPTUEX) Inner Range, Vieques, Puerto Rico. July 27, 2000.

Commander of the Navy (Navy), Atlantic Division, Naval Facilities Engineering Command. 2000b. Environmental Assessment for Transfer of the Naval Ammunition Support Detachment Property, Vieques, Puerto Rico. November 2000. Available from URL: www.navyvieques.navy.mil/navyvieques.default.htm .

Navy. 2001a. Installation restoration program: Community fact sheet. US Naval Ammunition Support Detachment, Vieques Island, Puerto Rico. Issue Number 2. April, 2001.

Eisenstein RS and Blemings KP. 1998. Iron regulatory proteins, iron responsive elements and iron homeostasis. The Journal of Nutrition 128: 2295-2298.

Environmental Protection Agency (EPA). 1991a. Toxicological review of cadmium. Washington, DC. January 1991.

EPA. 1991b. Toxicological review of selenium and compounds. Washington, DC. June 1991.

EPA. 1998. Toxicological review of hexavalent chromium. Washington, DC. August 1998.

EPA/Environmental Response Team (ERT). 1998. Fish Handling and Processing. Revision 0.0. Standard Operating Procedure #2039. April 10, 1998.

EPA. 2000. Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories. Volume 1: Fish Sampling and Analysis. November 2000. Available from URL: http://www.epa.gov/OST/fish/guidance.html.

EPA. 2001a. National Coastal Assessment Database. Environmental Monitoring and Assessment Program. Last updated: 7/30/2001. Available from URL: http://www.epa.gov/emap.

EPA. 2001b. Consumption Advise Fact Sheet: National Advice on Mercury in Fish Caught by Family and Friends: For Women Who Are Pregnant or May Become Pregnant, Nursing Mothers, and young Children. January 2001. Available from URL: http://www.epa.gov/waterscience/fishadvice/factsheet.html.

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US Food and Drug Administration (FDA). 1993. Guidance document for arsenic in shellfish. Department of Health and Human Services, Public Health Service, Food and Drug Administration, Center for Food Safety and Applied Nutrition. Washington, DC. January 1993. Available from URL: http://www.foodsafety.gov/~frf/guid-as.html.

FDA. 1997. Preventing iron poisoning in children. FDA Backgrounder. January 15, 1997. Available from URL: http://vm.cfsan.fda.gov/~dms/.

FDA. 2000. Is mercury in fish a safety concern? October 13, 2000. Available from URL: http://www.cfsan.fda.gov/~acrobat/hgadv8.pdf.

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FDA. 2001b. Mercury Levels in Seafood. May 2001. Available from URL: http://www.cfsan.fda.gov/~frf/sea-mehg.html.

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Navy - see Department of the Navy

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Young GA. 1978. Environmental dispersion of the products of explosions of conventional ordnance at Vieques Island, Naval Surface Weapons Center: August 28, 1978.

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Appendices A - C

Appendix A: ATSDR Glossary of Environmental Health Terms

Absorption: How a chemical enters a person's blood after the chemical has been swallowed, has come into contact with the skin, or has been breathed.

Acute Exposure: Contact with a chemical that happens once or only for a limited period of time. ATSDR defines acute exposures as those that might last up to 14 days.

Additive Effect: A response to a chemical mixture, or combination of substances, that might be expected if the known effects of individual chemicals, seen at specific doses, were added together.

Adverse Health Effect: A change in body function or the structures of cells that can lead to disease or health problems.

Antagonistic Effect: A response to a mixture of chemicals or combination of substances that is less than might be expected if the known effects of individual chemicals, seen at specific doses, were added together.

ATSDR: The Agency for Toxic Substances and Disease Registry. ATSDR is a federal health agency in Atlanta, Georgia that deals with hazardous substance and waste site issues. ATSDR gives people information about harmful chemicals in their environment and tells people how to protect themselves from coming into contact with chemicals.

Background Level: An average or expected amount of a chemical in a specific environment. Or, amounts of chemicals that occur naturally in a specific environment.

Biota: Used in public health, things that humans would eat - including animals, fish and plants.

Cancer: A group of diseases which occur when cells in the body become abnormal and grow, or multiply, out of control.

CEL: Cancer Effects Level. Dose that produces significant increases in the incidence of cancer or tumors.

Carcinogen: Any substance shown to cause tumors or cancer in experimental studies.

Chronic Exposure: A contact with a substance or chemical that happens over a long period of time. ATSDR considers exposures of more than one year to be chronic.

Completed Exposure Pathway: See Exposure Pathway.

Comprehensive Environmenta Response, Compensation, and Liability Act (CERCLA): CERCLA was put into place in 1980. It is also known as Superfund. This act concerns releases of hazardous substances into the environment, and the cleanup of these substances and hazardous waste sites. ATSDR was created by this act and is responsible for looking into the health issues related to hazardous waste sites.

Concern: A belief or worry that chemicals in the environment might cause harm to people.

Concentration: How much or the amount of a substance present in a certain amount of soil, water, air, or food.

Contaminant: See Environmental Contaminant.

Dose: The amount of a substance to which a person may be exposed, usually on a daily basis. Dose is often explained as "amount of substance(s) per body weight per day."

Dose / Response: The relationship between the amount of exposure (dose) and the change in body function or health that result.

Duration: The amount of time (days, months, years) that a person is exposed to a chemical.

Environmental Contaminant: A substance (chemical) that gets into a system (person, animal, or the environment) in amounts higher than that found in Background Level, or what would be expected.

Environmental Media: Usually refers to the air, water, and soil in which chemicals of interest are found. Sometimes refers to the plants and animals that are eaten by humans. Environmental Media is the second part of an Exposure Pathway.

US Environmental Protection Agency (EPA): The federal agency that develops and enforces environmental laws to protect the environment and the public's health.

Epidemiology: The study of the different factors that determine how often, in how many people, and in which people will disease occur.

Exposure: Coming into contact with a chemical substance.(For the three ways people can come in contact with substances, see Route of Exposure.)

Exposure Assessment: The process of finding the ways people come in contact with chemicals, how often and how long they come in contact with chemicals, and the amounts of chemicals with which they come in contact.

Exposure Pathway: A description of the way that a chemical moves from its source (where it began) to where and how people can come into contact with (or get exposed to) the chemical.

ATSDR defines an exposure pathway as having 5 parts:

1. Source of Contamination,
2. Environmental Media and Transport Mechanism,
3. Point of Exposure,
4. Route of Exposure, and
5. Receptor Population.

When all 5 parts of an exposure pathway are present, it is called a Completed Exposure Pathway. Each of these 5 terms is defined in this Glossary.

Frequency: How often a person is exposed to a chemical over time; for example, every day, once a week, twice a month.

Hazardous Waste: Substances that have been released or thrown away into the environment and, under certain conditions, could be harmful to people who come into contact with them.

Health Effect: ATSDR deals only with Adverse Health Effects (see definition in this Glossary).

Indeterminate Public Health Hazard: The category is used in Public Health Assessment documents for sites where important information is lacking (missing or has not yet been gathered) about site-related chemical exposures.

Ingestion: Swallowing something, as in eating or drinking. It is a way a chemical can enter your body (See Route of Exposure).

Inhalation: Breathing. It is a way a chemical can enter your body (See Route of Exposure).

MRL: Minimal Risk Level. An estimate of daily human exposure - by a specified route and length of time -- to a dose of chemical that is likely to be without a measurable risk of adverse, noncancerous effects. An MRL should not be used as a predictor of adverse health effects.

NPL: The National Priorities List. (Which is part of Superfund.) A list kept by the US Environmental Protection Agency (EPA) of the most serious, uncontrolled or abandoned hazardous waste sites in the country. An NPL site needs to be cleaned up or is being looked at to see if people can be exposed to chemicals from the site.

NOAEL: No Observed Adverse Effect Level. The highest dose of a chemical in a study, or group of studies, that did not cause harmful health effects in people or animals.

No Apparent Public Health Hazard: The category is used in ATSDR's Public Health Assessment documents for sites where exposure to site-related chemicals may have occurred in the past or is still occurring but the exposures are not at levels expected to cause adverse health effects.

No Public Health Hazard: The category is used in ATSDR's Public Health Assessment documents for sites where there is evidence of an absence of exposure to site-related chemicals.

PHA: Public Health Assessment. A report or document that looks at chemicals at a hazardous waste site and tells if people could be harmed from coming into contact with those chemicals. The PHA also tells if possible further public health actions are needed.

Plume: A line or column of air or water containing chemicals moving from the source to areas further away. A plume can be a column or clouds of smoke from a chimney or contaminated underground water sources or contaminated surface water (such as lakes, ponds and streams).

Point of Exposure: The place where someone can come into contact with a contaminated environmental medium (air, water, food or soil). For examples:

the area of a playground that has contaminated dirt, a contaminated spring used for drinking water, the location where fruits or vegetables are grown in contaminated soil, or the backyard area where someone might breathe contaminated air.

Population: A group of people living in a certain area; or the number of people in a certain area.

Public Health Hazard: The category is used in PHAs for sites that have certain physical features or evidence of chronic, site-related chemical exposure that could result in adverse health effects.

Public Health Hazard Criteria: PHA categories given to a site which tell whether people could be harmed by conditions present at the site. Each are defined in the Glossary. The categories are:

1. Urgent Public Health Hazard
2. Public Health Hazard
3. Indeterminate Public Health Hazard
4. No Apparent Public Health Hazard
5. No Public Health Hazard

Receptor Population: People who live or work in the path of one or more chemicals, and who could come into contact with them (See Exposure Pathway).

Reference Dose (RfD): An estimate, with safety factors (see safety factor) built in, of the daily, life-time exposure of human populations to a possible hazard that is not likely to cause harm to the person.

Route of Exposure: The way a chemical can get into a person's body. There are three exposure routes:

- breathing (also called inhalation),

- eating or drinking (also called ingestion), and

- or getting something on the skin (also called dermal contact).

Safety Factor: Also called Uncertainty Factor. When scientists don't have enough information to decide if an exposure will cause harm to people, they use "safety factors" and formulas in place of the information that is not known. These factors and formulas can help determine the amount of a chemical that is not likely to cause harm to people.

Source (of Contamination): The place where a chemical comes from, such as a landfill, pond, creek, incinerator, tank, or drum. Contaminant source is the first part of an Exposure Pathway .

Special Populations: People who may be more sensitive to chemical exposures because of certain factors such as age, a disease they already have, occupation, sex, or certain behaviors (like cigarette smoking). Children, pregnant women, and older people are often considered special populations.

Statistics: A branch of the math process of collecting, looking at, and summarizing data or information.

Synergistic effect: A health effect from an exposure to more than one chemical, where one of the chemicals worsens the effect of another chemical. The combined effect of the chemicals acting together are greater than the effects of the chemicals acting by themselves.

Toxic: Harmful. Any substance or chemical can be toxic at a certain dose (amount). The dose is what determines the potential harm of a chemical and whether it would cause someone to get sick.

Toxicology: The study of the harmful effects of chemicals on humans or animals.

Tumor: Abnormal growth of tissue or cells that have formed a lump or mass.

Uncertainty Factor: See Safety Factor.

Urgent Public Health Hazard: This category is used in ATSDR's Public Health Assessment documents for sites that have certain physical features or evidence of short-term (less than 1 year), site-related chemical exposure that could result in adverse health effects and require quick intervention to stop people from being exposed.

Appendix B: Sampling Methods for ATSDR's Fish and Shellfish Investigation

Sampling Techniques

At each location, field personnel collected fish and shellfish using the following methods:

• Spearfishing. Divers used spearguns, aided by self-contained underwater breathing apparatus (SCUBA), to collect fish. Where possible, the divers aimed for the fish's abdomen to avoid damaging the body meat (see Picture 11).
• Fishing poles. While on board the surface support boat, field personnel used fishing poles baited with squid.
• Hand capture. Lobster and conch were collected by hand, while snorkeling or while using SCUBA. Fiddler crabs were also collected by hand.
• Traps. Large wooden traps baited with fruit (e.g., mangos) were used to capture land crabs (see Picture 12).
• Field purchase. Field personnel purchased fish and lobsters from a local fish market. No attempt was made to verify the area from which the fish and lobsters were caught, though the market staff stated that all fish and lobsters sold in the market were caught locally.

Fish identifications were made using the field guide "Reef Fish Identification; Florida, Caribbean, Bahamas" (Humann 1994) and invertebrate identifications were made using the field guide "Caribbean Reef Invertebrates and Plants" (Colin 1978).

An attempt was made to collect organisms of the same approximate size (by species) at each location so that final tissue concentrations would be comparable. Because the reefs around Vieques are heavily fished, many of the fish and shellfish collected by field personnel were small, and it was not possible to collect five individuals of each of the species at every sampling location, as originally planned. Though yellowtail snapper was listed as the most commonly caught and consumed fish in Vieques (Caro et al. 2000), few yellowtail snappers were seen at any of the sampling locations, and those that were approachable were quite small (less than 30 cm).

The Caribbean Fishery Management Council size regulations were observed where possible (see text box for details). Because the field sampling trip was scheduled for mid-July, during the closed season for collecting queen conch and land crabs, field personnel were not able to abide by the seasonal regulations. The Puerto Rico Department of Natural and Environmental Resources (DNER), however, granted permission to collect these specimens.

Organism Collection

Fish and shellfish were collected using the commercial dive charter boat, "Moonglow," operated by the Blue Caribe Dive Center, in Esperanza, Vieques (see Picture 13). The captain made suggestions regarding specific reefs at the desired sampling locations. Reef names, where known, were supplied by the boat captain. Areas unfamiliar to the captain, and/or not named on nautical charts, were named (for the purposes of this study) by field personnel. The latitude and longitude of the approximate center of each sampling location was determined using a global positioning system (GPS) unit made available on the chartered dive boat. Fish and shellfish were collected from July 16-20, 2001. Sample locations are depicted in Figure 3.

• On the first sampling day, field personnel traveled to Location 3. Dives were made on Bucky Reef and Patti Reef, which are regularly visited by recreational divers and fisherman. Fish were collected using spearguns and a single lobster was collected by hand.
• On the second sampling day, field personnel traveled to Location 2. Dives were made on the former USS Killen. Fish were collected using spearguns and fishing poles, and conch were collected by hand. Field personnel were unsuccessful in their attempt to collect lobster from Location 2. Land crabs and fiddler crabs were collected from the shore area adjacent to the former USS Killen.
• On the third sampling day, field personnel traveled to Location 1. Dives were made on two small, unnamed reefs. The first small unnamed patch reef (North LIA 1) was visible from the surface, since the reef crest was partially emergent at low tide. The other reef (North LIA 2) was located by towing a diver behind the boat (see Picture 14). Fish were collected using spearguns and fishing poles, lobster and conch were collected by hand. Land crabs and fiddler crabs were collected from the shore area adjacent to the patch reef at North LIA 1.
• On the fourth sampling day, field personnel traveled to Location 4. Dives were made on two unnamed reefs (Isabel 1 and Isabel 2) and under a dock near the end of the Mosquito Pier. Fish were collected using spearguns and fishing poles. Field personnel were unsuccessful in their attempt to collect lobster and conch from Location 4.
• On the fifth sampling day, field personnel split into two teams. The first team traveled to Locations 3, 5, and 6. At Location 6, dives were made on an unnamed reef (West End). Fish were collected using spearguns and conch were collected from a nearby seagrass bed by hand. Field personnel were unsuccessful in their attempt to collect lobster from Location 6. On the return trip from Location 6 to Esperanza, field personnel stopped at Location 3 (Arena Reef) to collect conch. The second team retrieved land crabs from traps that had been set the previous day on land near Location 6 and purchased fish from a fish market in Isabel Segunda (Location 5).

Tissue Sampling

Fish were processed according to EPA's Standard Operating Procedure # 2039 Fish Handling and Processing (EPA/ERT 1998). Each fish was weighed, measured for total length, and observed both externally and internally for obvious abnormalities (e.g., neoplasms, parasites, deformities) (see Pictures 15 and 16). Fish were filleted, taking care not to include any portion of the meat that had been damaged by the spear, and a sample of the fillet was wrapped in plastic wrap, placed in a sealable plastic bag, and placed on wet ice until it could be frozen (in less than 6 hours). Sometimes fillets from both sides of the fish were collected in order to obtain sufficient tissue mass for analytical requirements.

Each lobster was weighed whole, measured for carapace length, and observed externally for obvious abnormalities. Lobster abdomens (i.e., tails) were separated from the carapace and the meat removed. The entire tail meat sample was wrapped in plastic wrap, placed in a plastic bag, and placed on wet ice until it could be frozen (in less than 6 hours).

Each conch was weighed (in its shell), measured for total shell length, and observed externally and internally for obvious abnormalities (see Pictures 17 and 18). Conch were removed from their shells by punching a hole in the shell at the second or third spire whorl, cutting the animal's attachment with a fillet knife, and pulling the animal out of the shell by its operculum. The conch meat was then separated from the operculum, mouth and eyes, and internal organs, wrapped in plastic wrap, placed in a plastic bag, and placed on wet ice until it could be frozen (in less than 6 hours).

The sex of the land crabs was recorded and the crab meat was "picked" from the chelipeds and the body (see Pictures 19 and 20). Since a single crab could not supply enough easily picked meat to meet the sample quantity needed for chemical analyses, the meat from several crabs was composited until a sufficient quantity of meat was obtained. Land crab composite samples were made from an equal number of male and female crabs. The meat was wrapped in plastic wrap, placed in a plastic bag, and placed on wet ice until it could be frozen (in less than 6 hours).

Fiddler crabs were analyzed for whole body burdens; therefore, they were weighed en masse to ensure a sufficient sample was collected for analysis. Though fiddler crabs were not individually weighed or measured, notes were made of obvious external abnormalities. Rinsing fiddler crabs of sand and dirt was inadvertently omitted prior to placing them into sample containers. The composite sample of crabs was placed in a plastic bag and placed on wet ice until it could be frozen (in less than 6 hours).

Tissue Analysis

All tissue samples were shipped on dry ice, via overnight delivery to EPA's subcontracted laboratory, Compuchem, for analysis of heavy metals, explosives compounds, percent lipids, and percent moisture. One gram tissue samples were analyzed for heavy metals according to EPA Method 6010B (utilizing inductively coupled argon plasma-atomic emission spectrometry and co-vapor atomic absorption; the method description can be found at the following URL: http://www.epa.gov/epaoswer/hazwaste/test/6010b.pdf). Two gram tissue samples were analyzed for explosives compounds according to EPA Method 8330 (utilizing high performance liquid chromatography; the method description can be found at the following URL: http://www.epa.gov/epaoswer/hazwaste/test/8330.pdf>). One specimen of each of the four species purchased from the fish market (red hind, white grunt, yellowtail snapper, and spiny lobster) was submitted to Brooks Rand Ltd. for separate methylmercury analysis. Methylmercury was determined using Brooks Rand method BR-0011 (utilizing aqueous phase ethylation, Tenax trap collection, gas chromatograph separation, isothermal decomposition, and cold vapor atomic fluorescence spectroscopic detection).

Quality Control

A qualified third party validator, the Response, Engineering and Analytical Contract (REAC), validated the results from the labs.

Metals analysis. Matrix spike/matrix spike duplicates were performed for the metals analysis. Percent recoveries ranged from 42 to 118; all 272 values were within acceptable quality control (QC) limits. The relative percent differences ranged from zero to two; all 136 values were within the acceptable QC limits. Laboratory duplicates were analyzed; relative percent differences ranged from zero to 154. A laboratory control sample standard was analyzed for each data package; percent recoveries ranged from 54 to 116.

Explosives Analysis. Matrix spike/matrix spike duplicates were performed for the explosives analysis. Percent recoveries ranged from 0 to 142; 178 or 192 values were within acceptable QC limits. The relative percent differences ranged from zero to 101; 88 of 93 values were within the acceptable QC limits. A laboratory control sample standard was analyzed for each batch. Percent recoveries ranged from 8 to 154; 90 of 96 values were within the acceptable QC limits. Each sample was spiked with 1,4-dinitrobenzene (surrogate) prior to extraction. The surrogate percent recoveries ranged from 63 to 158; 153 of 154 vales were within acceptable QC limits. The data associated with the only explosives compound detected, HMX, in fiddler crabs, fell within acceptable QC limits.

Appendix C: Conditions of the Reef

The following general reef conditions were noted by the lead Marine Scientist during ATSDR and EPA/ERT's fish and shellfish sampling. He is a certified diver with over 20 years experience diving on coral reefs, with formal training at the West Indies Laboratory (St. Croix, US Virgin Islands) in scientific diving, coral reef biology, and tropical marine ecology. Throughout his career he has made more than 500 dives on Caribbean reefs and seagrass beds in the Florida Keys, the US and British Virgin Islands, the Cayman Islands, St. Martin, and Vieques. His Master's degree focused on natural and anthropogenic stresses to seagrass beds and assessing population dynamics of resident green sea turtles. In addition, he managed an aquatic toxicology laboratory that studied the effects of environmental pollution to freshwater and marine fish, invertebrates, and plants and assisted the National Park Service and EPA with coral disease monitoring studies in St. John and St. Croix, respectively.

General

When comparing the sampling locations, it is important to note that the different locations exhibited varied depths, bottom structures (e.g., reef, rubble, wreck), currents, and fishing pressures. All descriptions of the appearance and general health of the sampling locations are subjective. No quantitative data were collected on the numbers of species or the number of individuals of each coral or fish species observed. In general, it appeared that all sample locations supported diverse, healthy populations of marine organisms. The impression of each of the divers was that the reefs were in good condition and that the fish appeared healthy.

All of the reefs and structures that were bordered by seagrass beds were surrounded by a sandy "halo" and then a healthy seagrass bed that was dominated by turtle grass (Thalassia testudinum). The halo is a typical feature of reefs and underwater structures that is caused by grazing organisms (most commonly the sea urchin, Diadema antillarum) leaving the shelter of the reef at night to feed on the surrounding seagrass beds (see Picture 21). Lack of a halo would have been indicative that grazers were not present. Turtle grass is the climax species in the succession from bare sand to algae to seagrass, and a dense bed of turtle grass is an indication of a mature, healthy system (McRoy and Helfferich 1977; Zieman and Zieman 1989).

At Locations 1, 2, and 6, many conch shells were found that had holes punched out by fishermen who pulled the meat out and threw the shells back before leaving the area. A number of holed shells were clearly not of legal size. Location 3 had a healthy population of conch, most likely because it was significantly deeper and; therefore, less accessible than the other locations.

At all sampling locations fish were plentiful and appeared to be in good health, but were generally small and wary of divers. Larger individuals appeared to be heavily fished from the reefs around Vieques.

At the Mosquito Pier location, the remains of a freshly butchered green sea turtle (Chelonia mydas) were found. The turtle was quite small, definitely immature, and all that was left was the neatly cut away plastron, still attached to the foreflippers. Since the green sea turtle is an endangered species and is protected by federal law, the finding was reported to the Puerto Rico Department of Natural and Environmental Resources (DNER). While green sea turtles are a common inhabitant of seagrass beds throughout the Caribbean, they were conspicuously absent from the seagrass beds during the dives conducted for this study.

Location 1

The first unnamed reef visited on the north shore of the LIA was a small, shallow, well developed patch reef, labeled "North LIA 1" by field personnel. The reef appeared to be in good health, with a diverse population of corals and fish. The reef was shallow, from 5 meters to emergent, composed of large head corals (e.g., Montastrea sp. and Diploria sp.) and soft corals (e.g., gorgonians and sea fans), with a lot of structure (hiding places for reef organisms) (see Pictures 22, 23, and 24). The reef was surrounded by a halo and a healthy turtle grass bed. Conch were collected in the turtle grass, but were very sparse and only a few legal sized specimens were found. Unexploded ordnance was visible in the seagrass bed.

The second unnamed reef visited on the north shore of the LIA was a small barrier type reef, extending east to west for approximately 250 meters from a small island, and labeled "North LIA 2" by field personnel. The reef was shallow, to a depth of 7 meters, but had relatively high relief (3 to 5 meters off the sand) and good structure. The reef appeared to be in good health, with a diverse population of corals and fish. On the shore side of the reef, there was a narrow halo and a healthy turtle grass bed. No ordnance was observed in this area. Field personnel did not dive on the seaward side of the reef.

Location 2

The first section of the former Navy vessel visited, on the south shore of the LIA, is in approximately 8 meters of water and is home to a diverse population of fish, all of which appeared to be healthy. One section had high relief (approximately 5 meters off the sand) but the smooth sides and top offered no habitat. Nonetheless, dozens of several different kinds of fish were seen inside that section. The other sections ranged from flat plates to broken sections with a lot of structure for fish habitat. There was a spotty distribution of small head corals (e.g., Montastrea sp., and Diploria sp.) growing on the surfaces of the wreck exposed to current and sunlight. All corals observed appeared to be in good health. The wreck was surrounded by a large halo and a healthy turtle grass bed. Unexploded ordnance was a common sight around the wreck and in the surrounding seagrass bed.

The second portion of the vessel was a large structure which provided habitat for fish. Located approximately 100 meters southeast of the first portion, it is also in about 8 meters of water and is home to a diverse population of apparently healthy fish. The ship offered high relief (approximately 5 to 6 meters off the sand), with a lot of structure for fish habitat. There was a spotty distribution of small, healthy head corals growing on the surfaces of the wreck which were exposed to current and sunlight (see Pictures 25 and 26). The wreck was surrounded by a large halo and a healthy turtle grass bed. Conch were collected in the halo area and the seagrass bed. Unexploded ordnance was a common sight around the wreck and in the surrounding seagrass bed.

Location 3

The first reef visited on the south shore near the town of Esperanza was Bucky Reef. The reef was approximately 18 meters deep and had high relief (5 to 7 meters off the sand), with a lot of structure. The reef appeared to be in good health, with a diverse population of both corals and fish. The top of the reef was mainly soft corals (e.g., gorgonians and sea fans) interspersed with small head corals, while the base of the reef had numerous holes and undercut ledges for fish habitat. The ocean bottom near the reef was coarse sand with some coral rubble.

The second reef visited on the south shore near Esperanza was Patti Reef. The reef was approximately 10 meters deep and had a lower profile than Bucky Reef, with isolated head corals and less structure. There were many healthy soft corals and a wide diversity of fish. The reef was spread out over a large area and the ocean bottom was sand and rubble. Most of the fish observed on this reef were small, probably a result of the lack of hiding places suitable for use as refuge from predators.

The third area visited was the seagrass area inshore of Arena Reef, in approximately 15 meters of water. The seagrass bed was sparse, but there were quite a few large conch present.

Location 4

The first reef visited on the north shore near the town of Isabel Segunda was an unnamed reef that field personnel labeled "Isabel 1." The reef was shallow, from 5 meters to emergent, and it was similar in structure to Patti Reef, with a low profile and many healthy soft corals. The isolated head corals and numerous fish all appeared healthy. The reef was spread out over a large area and the bottom was sand and rubble (see Picture 27).

The second reef visited on the north shore near the town of Isabel Segunda was also unnamed, and was called "Isabel 2" by field personnel. The reef was growing on a gradual slope that rose from a sand flat at approximately 13 meters deep to approximately 3 meters deep. The sand flat demonstrated the typical halo away from the reef into a seagrass bed. The reef had a lot of structure and supported a diverse, healthy population of hard and soft corals and fish (see Pictures 28 and 29).

The third location visited on the north shore near the town of Isabel Segunda was Mosquito Pier. The pier is a large earthen structure extending approximately one-half mile to the north from land. In order to accommodate large vessels a dock extends to the west, near the end of the pier, into approximately 13 meters of water. Diving to collect fish was limited to the area under the dock. The dock had a lot of structure, mostly concrete rubble, at its origin and supported a large population of small fish. Toward the end of the dock, there was very little bottom structure except for the dock pilings. There were no hard corals present, though the pilings displayed nearly complete encrustation with a diverse population of invertebrate and plant life.

Location 6

The unnamed reef visited on the west end of the island was southwest of the Monte Pirata Conservation Zone, labeled "West End" by field personnel, and was in 20 meters of water. The reef was a spur and groove type reef with low relief (less than 3 meters off the sand), but had a lot of structure for fish. Spur and groove reefs are characterized by a series of long (100 meters), usually narrow (7 meters wide) coral spurs, with a narrow (7 meters wide) bare sand channel between each spur. The reef had diverse, apparently healthy, populations of corals and fish. The tops of the spurs had many soft corals and small head corals, and the bottom of the spurs had many small holes and undercuts for fish habitat.

Conch were collected from a healthy turtle grass bed approximately 500 meters northeast of the reef in approximately 7 meters of water. Conch were plentiful, but most visible animals were below legal size.

Appendix F

Pictures Referenced in the Public Health Assessment

Picture 1. West Vieques

Picture 2. Former Eastern Maneuver Area

Picture 3. OP-1 in the Atlantic Fleet Weapons Training Facility

Picture 4. Atlantic Fleet Weapons Training Facility

Picture 5. Former Live Impact Area

Picture 6. Targets in the Live Impact Area

Picture 7. Punta Este Conservation Zone

Picture 8. Isabel Segunda

Picture 9. Esperanza

Picture 10. Mosquito Pier

Picture 11. EPA/ERT Diver Spearfishing

Picture 12. Land Crab Trap

Picture 13. The Moonglow

Appendix F Continued

Pictures Referenced in the Public Health Assessment

Picture 15. Measuring Fish Length

Picture 16. Filleting Fish

Picture 17. Measuring Conch Length

Picture 18. Weighing Conch

Picture 19. Picking Land Crabs

Picture 20. Land Crabs

Picture 21. Sea Urchin

Picture 22. Hard Coral

Picture 23. Hard Coral

Picture 24. Soft Coral

Picture 25. Coral on Sunken Navy Target Vessel

Picture 26. Coral on Sunken Navy Target Vessel

Picture 27. Fish around Coral Reef

Picture 28. Corals and Fish from Location 4

Picture 29. Corals and Fish from Location 4

Appendix G

Response to Public Comments

The Agency for Toxic Substances and Disease Registry (ATSDR) received the following comments during the public comment period (November 14, 2002 to January 27, 2003) for the Fish and Shellfish Evaluation for the Isla de Vieques Bombing Range Public Health Assessment (PHA) (November 2002). For comments that questioned the validity of statements made in the PHA, ATSDR verified or corrected the statements. The list of comments does not include editorial comments, such as word spelling or sentence syntax.

1. Comment: Between this fish and shellfish evaluation and the earlier groundwater and drinking water pathways et al studies I consider the inhabitants of Isla de Vieques to be in a reasonably safe environment.

   Response: Thank you for the comment. After thoroughly evaluating the drinking water and groundwater supplies, the soil pathway, the fish and shellfish, and the air pathway, ATSDR agrees that the residents of Vieques are not being exposed to harmful levels of chemicals from the Live Impact Area (LIA).

2. Comment: While stated in different parts of the document, the document summary should name the metals found in the fish and shellfish and conclude that while the following compounds were found to be present in the fish and shellfish of Vieques, they are found at levels low enough as not to pose a threat to human health. The individual metals found should also be included in Part VIII, Conclusion.

   Response: ATSDR agrees with the statement that while metals were detected in the Vieques fish and shellfish, they were found at levels too low to present a public health concern. However, since very few metals were not detected in Vieques fish and shellfish, listing all of them would not be efficient. Instead, please refer to Tables 8 and 9 which identify the ranges, averages, and frequency of detections for the metals that were detected in the fish and shellfish, respectively. It should be noted that heavy metals are commonly detected in fish and shellfish tissue because seafood tends to accumulate metals that are naturally present in the environment.

3. Comment: The report should have one or two sentences stating that the findings of this report are directed solely at human health and cannot be used to infer ecological integrity of the natural systems on Vieques. The results of an ATSDR report should not be used to imply that there are no environmental impacts on Vieques.

   Response: ATSDR agrees that this evaluation is a public health assessment, not an ecological assessment.

4. Comment: The importance of how explicit appear the text is to determine the existence or not of the contamination and the pathways.

   Response: ATSDR agrees that it is important to explicitly present the findings about the existence of contamination and the possibility of exposure pathways.

5. Comment: The PHA is strongly based on Dr. Caro's research, Metropolitan University. While Dr. Caro's report determines that her research is a starting point; inclusive without having access to the complete methodology of the research, I question that epidemiologically, 51 residents are a representative percentage of the total population of Vieques Island.

   Response: At the time of ATSDR's sampling, Dr. Caro's research provided the most detailed and relevant information about consumption habits of Vieques residents (Caro et al. 2000). However, it was not the only source consulted by ATSDR. We also relied on information provided by (1) the petitioner, (2) the Vieques Special Commission Report (Government of Puerto Rico 1999 as cited in Navy 2000b), (3) ATSDR's community involvement program, and (4) visits to local fish markets by ATSDR staff. Taken together, these sources provided ATSDR with a good indication of how often residents of Vieques eat fish and shellfish and what species they eat.

6. Comment: Epidemiologically does not establish the absence of risk.

   Response: ATSDR assumes that this comment is in reference to Dr. Caro's research of a representative sampling (51 people) of Vieques residents' consumption habits (Caro et al. 2000). Dr. Caro's research helped ATSDR determine which species of fish and shellfish to collect and helped determine how often residents of Vieques ate fish and shellfish. The information provided in the report was substantiated by information collected by the petitioner, ATSDR's community involvement program, the Vieques Special Commission Report (Government of Puerto Rico 1999 as cited in Navy 2000b), and visits to local fish markets.

   To determine whether it is safe to eat the fish and shellfish from around Vieques, ATSDR collected 104 fish and 38 shellfish and analyzed them for heavy metals and explosive compounds. The results of the sampling and analysis indicated what levels of chemicals are present in the fish and shellfish around Vieques. ATSDR used these data to determine that it is safe for people to eat fish and shellfish with the detected levels of chemicals.

7. Comment: The methodology by which the nutritional information is obtained is unclear.

   Response: To determine which species of commonly consumed fish should be sampled, ATSDR compiled consumption information from the questionnaire administered by the Universidad Metropolitana researchers (Caro et al. 2000), the petitioner, the Vieques Special Commission Report (Government of Puerto Rico 1999 as cited in Navy 2000b), ATSDR's community involvement program, and visits to local fish markets by ATSDR staff.

   1. Some of the information regarding the relative frequency of consumption by Viequenses was obtained from the study done by Metropolitan University (Caro et al. 2000). As quoted by the ATSDR, a total of 51 Viequenses was surveyed in Dr. Caro's study and the frequency of fish consumption was derived from this survey. The age and sex distribution of the 51 subjects is not known.

   Response: The 51 residents of Vieques who were questioned by Universidad Metropolitana were comprised of 20 females (39.2%) and 31 males (60.8%). While the researchers did not report the actual ages of the residents who participated in the questionnaire, they did ask how long they lived in Vieques. Eleven people (21.5%) reported that they lived in Vieques 1-10 years, 9 people (17.6%) lived in Vieques 11-20 years, 10 people (19.6%) lived in Vieques 21-35 years, and 21 people (41.2%) lived in Vieques 36 or more years. This information is provided in the original report (Caro et al. 2000).

   1. The potential consumption of seafood (fish, mollusks, and/or crustaceans) more than once daily is not contemplated in the Dr. Caro study:

   fish consumed % (of subjects)	frequency
   47.05	1-2 times per week
   17.60	3-4 times per week
   15.60	5 or more times per week
   19.60	0 or occasional

Response: It appears that the Universidad Metropolitana researchers asked how many times a week the residents ate seafood. This seems to imply that a person could respond with a number greater than seven if they ate fish or shellfish more than once a day. The category of "5 or more times per week" would; therefore, include anyone who eats fish or shellfish more than once a day.

¹² EPA's Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories suggests collecting one species of fish and one species of shellfish when trying to assess whether a potential human health risk exists for estuarine/marine environments (EPA 2000).

¹³ EPA's Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories suggests collecting one species of fish and one species of shellfish when trying to assess whether a potential human health risk exists for estuarine/marine environments (EPA 2000).

¹⁴ Median total mercury concentration in 350 fish sampled from 25 species consumed by the Seychellois was <1 ppm (range, 0.004-0.75 ppm).